How to Return and Unset the References in PHP?

[Silent~Kid]

Hello friends,
I have done some basic coding in PHP and I am not an expert in that. I need some help from you guys like you always do.!! Recently I have started with the topic of references. I have got some points of references. But now I told to do the unset and I have to return the references which I don't know how to do.!! Please tell me how to Return and Unset the References in PHP? Hoping that someone would reply soon.!!

[Warner]

I think that before returning and unsetting the references, you should know more about the references which is important. As its name implies, a reference in PHP is a variable that "references" the contents of another variable. By using references, you can refer or point to the same data using different variables. When you trigger an exception, normally the following things are occurred.

• The code which is running currently is saved.
• The code execution will switch to a predefined exception handler function.
• Handler may then resume the execution from the saved code state, terminate the script execution or continue the script from a different location in the code and this all depends on the situation.

[Allan.d]

As usual you will have to write an exception in try and catch block. So that when an exception is thrown, the code following it will not be executed, and PHP will try to find the matching catch block. The following example has a proper code :

<?php
function CheckDemo($number)
  {
  if($number>5)
    {
    throw new Exception("Value must be 5 or below");
    }
  return true;
  }

try
  {
  checkNum(2);
  echo 'If you see this, the number is 5 or below';
  }

catch(Exception $e)
  {
  echo 'Message: ' .$e->getMessage();
  }
?>

[void]

When you want to use a function to find to which variable a reference should be bound then the returning by reference is useful. the main thing that you should keep in mind that not to use the return-by-reference to increase performance. Because the engine will automatically optimize this on its own. The following is an syntax to return references :

<?php
class call {
    public $value = 52;

    public function &getValue() {
        return $this->value;
    }
}

$obj = new call;
$myValue = &$obj->getValue();
$obj->value, which is 52.
$obj->value = 2;
echo $myValue;                
?>

[CodGuru]

When you want to unset the reference, you can do it just by breaking the binding between variable name and variable content. you have not to worry about because by doing this variable content will not be destroyed. I have provided an example that explains the same :

<?php
$a = 3;
$b =& $a;
unset($a); 
?>

The above coding won't unset $b, just $a.